Muffler



P 1943- A. G. BERGMANN 2,317,246

MUFFLER Filed June 10, 1941 ATTORNEY.

Patented Apr. 20, 1943 UNITED STATES' PATENT OFFICE MUFFLER Adolph G. Bergman, Ammo ia, Conn, Application June 10, 1941, Serial No. 397,443

This invention relates to exhaust muiiiers of the type commonly used for muilling the exhaust gases 01' internal combustion engines.

An object of the invention is to provide such a mufllerwhich is highly efilcient and which has a minimum of resistance to the passage of the exhaust gases therethrough and thereby reducing counter-pressure to a minimum as compared with muillers heretofore produced.

- A further object of this invention is to provide a muiller having Spiral passages for conducting the exhaust gases through the mufiler with s. rotary movement and reversing the direction of said movement to diminish the velocity of the gases and thereby practically eliminate detonation as the gases reach the atmosphere.

A still further object of the invention is to provide means in such a mufiler whereby the gases are guided smoothly, and without sudden obstruction, into the spiral passages to eliminate abrupt changes in the direction of their travel which would tend to create counter-pressure.

These and further objects of the invention will be more clearly understood from the following 8 Claims. (Cl. 181-86) In the operation of my improved muiiier, the exhaust gases move through the muiiler in the direction indicated by the arrows shown in the drawing.

As the gases enter into the chamber ll, between the' front end 'member 8 and the has 8, they are directed into the passages Ill through the straight passages it formed by the straight portions ll of the fins. The said passages ll are gradually blended into the passages l0, by the curved portions ll-a in the fins, to gently start rotation of the gases into the passages I ll without abruptly interrupting their travel with undue resistance which would cause counter pressure.

When the said gases reach the end of the pas sages III, they enter the mixing chamber ll,

' which .is provided by the spacing l6, and then This invention contemplates the use of a multi- 4o plicity of spiral fins I which surround a central core 8 so as to form spiral passages II leading in one direction for a portion of the distance through the tubular member I, and similar fins ll surrounding a core l2 and forming spiral enter the spiral passages ll whereby they are revolved in the opposite direction until they reach the straight passages 2| in which the direction of travel of said gases will be straightened out to prevent swirling motion before they enter the chamber 2i, wherein they are again mixed, and from which they will pass out of the muiller through the pipe section 'l-a.

My invention therefore provides a muiller which, in its operation, will, respectively, gently guide the exhaust gases into a spiral path, revolve them in one direction to check their speed, mix them to break up currents, revolve them in an opposite direction to further check their speed, straightenout their passage to prevent swirling. again mix them to eliminate fiuttering of the gases as they pass into the atmosphere, and then eject them from the muiller in a silent uniform fiow.

I have found that noise and vibration, caused by the gases passing through the muiller, may be eliminated, without the use of bafile plates or similar obstructions, by dividing the interior of the mufiler into a multiplicity of passages, of not less than ten in number, so as to separate the gases into relatively fine parallel streams; I have also found that the back pressure, which is commonly caused in muillers where baiiles are used and the gases are thereby violently disrupted in their movement through the muiller, will be practically eliminated by omitting such I bame plates and providing my-improved means for smoothly guiding the gas streams into the mumer in a straight direction, then gradually and gently swerving them into a spiral direction as and again gently and gradually bringing them bag; into a straight direction before leaving the m er.

It may therefore be seen that my invention provides a novel and highly efllclent muiller structure which will operate to exhaust engine gases silently and practically without back pressure. The said operation being rendered possible by the division oi. the gases into more than ten 7 separate streams and the guiding of said streams smoothly through the mui'iler, which makes unnecessary the use of baflles.

I claim: 1

-1. A muiiler oi! the character described comprising an elongated tubularcasing containing therein a plurality of .flns forming spiral passages through said casing; the ends of said fins being straight for a distance to provide straight passages leading into the spiral passages.

. 2. An exhaust muilier of the character described comprising a casing having a plurality of fins forming passages for exhaust gases thereprising a tubular casing having fins therein providing a plurality of passages for dividing gases passing through said muflier, each of said fins each including a spirally extending portion and a contiguous straight portion.

5. A mufiler of the characterdescribed comasmaas I prising a tubular casing having fins therein pro casing.

'7. A-mufiier of the character described comprising a tubular casing having means therein forming a plurality of passages for dividing gases into at least ten separate streams and guiding said streams through said mufller in spiral di-.

rections.

8. An exhaust muflier of the character described comprising a tubular casing containing therein and at one end thereof passage forming means including a core, a multiplicity of fins extending around said core for the entire length thereof, the said fins having a straight portion adjacent the end of said casing and a spiral portion continuing from said straight portion, a similar core at the opposite end of said casing spaced from the first core and having similar fins each with a spiral portion extending in an opposite direction to the spiral portion of the first core; the second fins each havinga straight portion adjacent the opposite end of the casing and continuing from the spiral portion thereof.

ADOLPH G. BERGMANN. 

